This is possible but you will have to resort to possibly some used equipment. The gpu and ram are the most hardest to find at a decent price. I can get 8gb sticks of ddr4 ram for 75 a piece shipped. There Kingston value ram but they work.
but the hp power desktop from walmart my man, i5 with a gtx 1060. it was 499.99 but it’s about 600 right now. that would be your best option. or buy all of your parts brand new and buy a used gpu then that would also work